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Topic Review
Inertial Confinement Fusion
Inertial confinement fusion (ICF) is a type of fusion energy research that attempts to initiate nuclear fusion reactions by heating and compressing a fuel target, typically in the form of a pellet that most often contains a mixture of deuterium and tritium. Typical fuel pellets are about the size of a pinhead and contain around 10 milligrams of fuel. To compress and heat the fuel, energy is delivered to the outer layer of the target using high-energy beams of laser light, electrons or ions, although for a variety of reasons, almost all ICF devices (As of 2015) have used lasers. The heated outer layer explodes outward, producing a reaction force against the remainder of the target, accelerating it inwards, compressing the target. This process is designed to create shock waves that travel inward through the target. A sufficiently powerful set of shock waves can compress and heat the fuel at the center so much that fusion reactions occur. ICF is one of two major branches of fusion energy research, the other being magnetic confinement fusion. When it was first proposed in the early 1970s, ICF appeared to be a practical approach to power production and the field flourished. Experiments during the 1970s and '80s demonstrated that the efficiency of these devices was much lower than expected, and reaching ignition would not be easy. Throughout the 1980s and '90s, many experiments were conducted in order to understand the complex interaction of high-intensity laser light and plasma. These led to the design of newer machines, much larger, that would finally reach ignition energies. The largest operational ICF experiment is the National Ignition Facility (NIF) in the US, designed using the decades-long experience of earlier experiments. Like those earlier experiments, however, NIF has failed to reach ignition and is, as of 2015, generating about ​1⁄3 of the required energy levels.
  • 4.1K
  • 29 Sep 2022
Topic Review
Blairism
In British politics, Blairism is the political ideology of the former leader of the Labour Party and Prime Minister Tony Blair and those that follow him. It entered the New Penguin English Dictionary in 2000. Proponents of Blairism are referred to as Blairites.
  • 4.1K
  • 18 Oct 2022
Topic Review
Action
In physics, action is a numerical value describing how a physical system has changed over time. Action is significant because the equations of motion of the system can be derived through the principle of stationary action. In the simple case of a single particle moving with a specified velocity, the action is the momentum of the particle times the distance it moves, added up along its path, or equivalently, twice its kinetic energy times the length of time for which it has that amount of energy, added up over the period of time under consideration. For more complicated systems, all such quantities are added together. More formally, action is a mathematical functional which takes the trajectory, also called path or history, of the system as its argument and has a real number as its result. Generally, the action takes different values for different paths. Action has dimensions of energy × time or momentum × length, and its SI unit is joule-second (like the Planck constant h).
  • 4.1K
  • 25 Nov 2022
Topic Review
Radio Direction Finder
A radio direction finder (RDF) is a device for finding the direction, or bearing, to a radio source. The act of measuring the direction is known as radio direction finding or sometimes simply direction finding (DF). Using two or more measurements from different locations, the location of an unknown transmitter can be determined; alternately, using two or more measurements of known transmitters, the location of a vehicle can be determined. RDF is widely used as a radio navigation system, especially with boats and aircraft. RDF systems can be used with any radio source, although the size of the receiver antennas are a function of the wavelength of the signal; very long wavelengths (low frequencies) require very large antennas, and are generally used only on ground-based systems. These wavelengths are nevertheless very useful for marine navigation as they can travel very long distances and "over the horizon", which is valuable for ships when the line-of-sight may be only a few tens of kilometres. For aircraft, where the horizon at altitude may extend to hundreds of kilometres, higher frequencies can be used, allowing much smaller antennas. An automatic direction finder, often capable of being tuned to commercial AM radio transmitters, is a feature of almost all modern aircraft. For the military, RDF systems are a key component of signals intelligence systems and methodologies. The ability to locate the position of an enemy transmitter has been invaluable since World War I, and it played a key role in World War II's Battle of the Atlantic. It is estimated that the UK's advanced "huff-duff" systems were directly or indirectly responsible for 24% of all U-boats sunk during the war. Modern systems often use phased array antennas to allow rapid beam forming for highly accurate results. These are generally integrated into a wider electronic warfare suite. Several distinct generations of RDF systems have been used over time, following new developments in electronics. Early systems used mechanically rotated antennas that compared signal strengths from different directions, and several electronic versions of the same concept followed. Modern systems use the comparison of phase or doppler techniques which are generally simpler to automate. Modern pseudo-Doppler direction finder systems consist of a number of small antennas fixed to a circular card, with all of the processing performed by software. Early British radar sets were also referred to as RDF, which was a deception tactic. However, the terminology was not inaccurate; the Chain Home systems used separate omnidirectional broadcasters and large RDF receivers to determine the location of the targets.
  • 4.1K
  • 10 Oct 2022
Topic Review
EPR (Nuclear Reactor)
The EPR is a third generation pressurised water reactor (PWR) design. It has been designed and developed mainly by Framatome (part of Areva between 2001 and 2017) and Électricité de France (EDF) in France, and Siemens in Germany. In Europe this reactor design was called European Pressurised Reactor, and the internationalised name was Evolutionary Power Reactor, but it is now simply named EPR. The first two EPR units, at Olkiluoto in Finland and Flamanville in France, are both facing costly construction delays (to at least 2019). Construction commenced on two Chinese units at Taishan in 2009 and 2010. Taishan 1 achieved criticality on 6 June 2018. Taishan 2 is expected to begin operation in 2019. Two units at Hinkley Point in the United Kingdom received final approval in September 2016 and are expected to be completed by 2025. EDF has acknowledged severe difficulties in building the EPR design. In September 2015 EDF stated that the design of a "New Model" EPR was being worked on, which will be easier and cheaper to build.
  • 4.1K
  • 15 Nov 2022
Topic Review
Content-Control Software
Content-control software, commonly referred to as an Internet filter, is software that restricts or controls the content an Internet user is capable to access, especially when utilised to restrict material delivered over the Internet via the Web, Email, or other means. Content-control software determines what content will be available or be blocked. Such restrictions can be applied at various levels: a government can attempt to apply them nationwide (see Internet censorship), or they can, for example, be applied by an ISP to its clients, by an employer to its personnel, by a school to its students, by a library to its visitors, by a parent to a child's computer, or by an individual user to their own computer. The motive is often to prevent access to content which the computer's owner(s) or other authorities may consider objectionable. When imposed without the consent of the user, content control can be characterised as a form of internet censorship. Some content-control software includes time control functions that empowers parents to set the amount of time that child may spend accessing the Internet or playing games or other computer activities. In some countries, such software is ubiquitous. In Cuba, if a computer user at a government-controlled Internet cafe types certain words, the word processor or web browser is automatically closed, and a "state security" warning is given.
  • 4.1K
  • 08 Nov 2022
Topic Review
Waste Cooking Oil for Biofuel in India
Waste or used cooking oil (WCO/UCO) is a common source of trans fat consumed by Indians, leading to many non-communicable diseases like diabetes, hypertension, cardiovascular diseases, stroke, cancer, etc. In fact, out of 230 million MT of edible oil consumption, India is currently capable of producing only 3 million MT of biodiesel. Moreover, with the increased emphasis on the circular economy to improve rural employment opportunities, India should adopt a complete exergy analysis of biodiesel production from WCO.
  • 4.1K
  • 20 Feb 2023
Topic Review
Exoskeletons
Exoskeletons are orthoses of a certain kind—devices that work in harmony and parallel with their users (humans) in order to augment physical performance and are able to complete certain tasks or movements. In order to achieve such coordination, the device must be fitted to the user’s dimensions. 
  • 4.1K
  • 12 Jan 2021
Topic Review
Levels-of-Processing Effect
The levels-of-processing effect, identified by Fergus I. M. Craik and Robert S. Lockhart in 1972, describes memory recall of stimuli as a function of the depth of mental processing. Deeper levels of analysis produce more elaborate, longer-lasting, and stronger memory traces than shallow levels of analysis. Depth of processing falls on a shallow to deep continuum. Shallow processing (e.g., processing based on phonemic and orthographic components) leads to a fragile memory trace that is susceptible to rapid decay. Conversely, deep processing (e.g., semantic processing) results in a more durable memory trace. This theory contradicts the multi-store Atkinson-Shiffrin memory model which represents memory strength as being continuously variable, the assumption being that rehearsal always improves long-term memory. They argued that rehearsal that consists simply of repeating previous analyses (maintenance rehearsal) doesn't enhance long-term memory. In a study from 1975 (Craik and Tulving) participants were given a list of 60 words. Each word was presented along with three questions. The participant had to answer one of them. Those three questions were in one of three categories. One category of questions was about how the word was presented visually ("Is the word shown in italics?"). The second category of questions was about the phonemic qualities of the word ("Does the word begin with the sound 'bee'?"). The third category of questions was presented so that the reader was forced to think about the word within a certain context. ("Can you meet one in the street [a friend]"?) The result of this study showed that the words which contained deep processing (the latter) were remembered better.
  • 4.1K
  • 25 Oct 2022
Topic Review
Coypu
The coypu (from spa coipú, from arn koypu; Myocastor coypus), also known as the nutria, is a large, herbivorous, semiaquatic rodent. Classified for a long time as the only member of the family Myocastoridae, Myocastor is now included within Echimyidae, the family of the spiny rats. The coypu lives in burrows alongside stretches of water, and feeds on river plant stems. Originally native to subtropical and temperate South America, it has since been introduced to North America, Europe, Asia, and Africa, primarily by fur farmers. Although it is still hunted and trapped for its fur in some regions, its destructive burrowing and feeding habits often bring it into conflict with humans, and it is considered an invasive species.
  • 4.1K
  • 04 Nov 2022
Topic Review
Network Intrusion Detection Systems Using Artificial Intelligence/Machine Learning
The rapid growth of the Internet and communications has resulted in a huge increase in transmitted data. These data are coveted by attackers and they continuously create novel attacks to steal or corrupt these data. The growth of these attacks is an issue for the security of systems and represents one of the biggest challenges for intrusion detection. An intrusion detection system (IDS) is a tool that helps to detect intrusions by inspecting the network traffic. Although many researchers have studied and created new IDS solutions, IDS still needs improving in order to have good detection accuracy while reducing false alarm rates. 
  • 4.1K
  • 23 Dec 2022
Topic Review
Cellulose Nanomaterials
Cellulose is the most abundant renewable source on Earth. Due to several of their characteristics, such as their renewability, sustainability, and eco-friendliness, nanocellulose-based materials are arousing growing interest from researchers in various fields of study and applications. 
  • 4.1K
  • 20 Dec 2022
Topic Review
Methanol to Gasoline (MTG)
The MTG (Methanol to Gasoline) process allows us to transform methanol into hydrocarbons within the range of gasoline boiling points.
  • 4.1K
  • 04 Mar 2022
Topic Review
Multi-Dimensional Concept of Sustainable Development and Urban Governance
Modern cities bear the entire burden and responsibility of operationalizing the concept of sustainable development, since they are the ones that represent the greatest threat to its implementation. The sustainability of cities largely depends on the form of public governance and decision making; in fact, this interdependence is a prerequisite for all the relevant progress in sustainable development that many European cities strive to achieve. An approach to governance in European cities that has proven to be the most effective in achieving urban sustainability is an integrated one, as it encompasses the coordination, cooperation and integration of sectoral policies and the participation of different actors at all levels of governance.
  • 4.1K
  • 16 Jun 2023
Topic Review
Sex Organ
A sex organ (or reproductive organ) is any part of an animal's body that is involved in sexual reproduction. The reproductive organs together constitute the reproductive system. The testis in the male, and the ovary in the female, are called the primary sex organs. All others are called secondary sex organs, divided between the external sex organs—the genitals or genitalia, visible at birth in both sexes—and the internal sex organs. Mosses, ferns, and some similar plants have gametangia for reproductive organs, which are part of the gametophyte. The flowers of flowering plants produce pollen and egg cells, but the sex organs themselves are inside the gametophytes within the pollen and the ovule. Coniferous plants likewise produce their sexually reproductive structures within the gametophytes contained within the cones and pollen. The cones and pollen are not themselves sexual organs.
  • 4.1K
  • 04 Nov 2022
Topic Review
Structure of the Earth
The internal structure of the Earth is layered in spherical shells: an outer silicate solid crust, a highly viscous asthenosphere and mantle, a liquid outer core that is much less viscous than the mantle, and a solid inner core. Scientific understanding of the internal structure of the Earth is based on observations of topography and bathymetry, observations of rock in outcrop, samples brought to the surface from greater depths by volcanoes or volcanic activity, analysis of the seismic waves that pass through the Earth, measurements of the gravitational and magnetic fields of the Earth, and experiments with crystalline solids at pressures and temperatures characteristic of the Earth's deep interior.
  • 4.1K
  • 26 Oct 2022
Topic Review
Histamine H1 Receptor Antagonists
Histamine H1 receptor (H1 receptor) antagonists are widely prescribed medications to treat allergic diseases, while recently it has emerged that they show significant promise as anti-SARS-CoV-2 agents.
  • 4.1K
  • 03 Jun 2021
Topic Review
Sting-Related Deaths in Europe (1994–2016)
Bees and wasps provide an important service to ecosystems, contributing to the improvement of biodiversity while helping to maintain ecological balance. Although not frequent, hornet, wasp, and bee stings may be life-threatening. With each sting, Hymenopterans inject a small amount of venom that can cause reactions of varying intensity: (i) normal local reactions (NLR), (ii) large local reactions (LLR), (iii) systemic anaphylactic reactions (SAR), (iv) systemic toxic reactions (STR) and (v) unusual reactions (UR).  Hymenopteran stings have recently become a worldwide public health concern. However, this health problem can be underestimated despite the number of cases presented. With the expansion of non-native Hymenopteran species across Europe, allergists should be aware that their community’s exposures are continually changing.
  • 4.1K
  • 28 Feb 2022
Topic Review
Tree of Life
The tree of life or universal tree of life is a metaphor, model and research tool used to explore the evolution of life and describe the relationships between organisms, both living and extinct, as described in a famous passage in Charles Darwin's On the Origin of Species (1859). {{Blockquote Tree diagrams originated in the medieval era to represent genealogical relationships. Phylogenetic tree diagrams in the evolutionary sense date back to the mid-nineteenth century. The term phylogeny for the evolutionary relationships of species through time was coined by Ernst Haeckel, who went further than Darwin in proposing phylogenic histories of life. In contemporary usage, tree of life refers to the compilation of comprehensive phylogenetic databases rooted at the last universal common ancestor of life on Earth. Two public databases for the tree of life are TimeTree, for phylogeny and divergence times, and the Open Tree of Life, for phylogeny.
  • 4.1K
  • 18 Oct 2022
Topic Review
Single Cell Protein
Single cell protein (SCP) is the first product of the fermentation process and has proven to be a good protein alternative. Food competition is becoming more intense as the world’s population continues to grow. Soon, SCP may be able to compensate for a protein deficit. Various global businesses are focusing on SCP production, and the scope of its application is expanding as time and knowledge increases.
  • 4.1K
  • 30 Aug 2021
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